The school behind the book, movie and TV series "Friday Night Lights" has had five staff members investigated for suspected sexual relations with students.

The school behind the book, movie and TV series "Friday Night Lights" has become mired in scandal with five staff members investigated for suspected sexual relations with students, including a teacher who died this week, a likely suicide.

Mark Lampman, 47, resigned as a government teacher on Tuesday from Permian High School in Odessa after the school in western Texas received an anonymous tip about an improper relationship between him and a student, school officials said.

"When they questioned him, that's when he turned in his resignation and left," district spokesman Mike Adkins said.

He was found dead Wednesday of an apparent self-inflicted gunshot wound to the chest, the Ector County Sheriff's Office said.

Lampman is the fifth staff member to be accused in the last year of having an inappropriate relationship with a student. One of those employees was later cleared of wrongdoing, school officials said.

In April 2013, a Permian swim coach and a trainer resigned and were later indicted on charges of improper relations between educator and student. Last month, a Permian employee also resigned amid claims made by parents to school district police of an inappropriate relationship with a student.

The staff members were not immediately available for comment.

The district said it was investigating the series of inappropriate teacher-student relationships.

"If we really knew why, we could address it directly and very quickly. It's not a satisfying answer for anybody involved — including us or the community — but we just don't know," Adkins said.

"Friday Night Lights" was a best-selling book about the celebrated role high school football plays in Texas that was later turned into a movie, and then used as the basis for a TV series.